Nitrox card required to dive, not just for fills?

[Overshoot]

Never mind ...

 

[MXGratefulDiver]

Sorry Bob, you're incorrect. NAUI Instructor's Manual 2.44 and 2.45 (top of the page) "May be taught by any active-status NAUI Instructor."

I'll have to look that up when I get home ... I don't have my standards manual with me at the moment. I do know that wasn't the case when I became an instructor in 2004.

What I've said IS true Bob. What you choose to believe is up to you. Perhaps you might ask yourself why the term Nitrox I is used and EAN32 isn't called Nitrox 32? It's just a terminology thing when you refer to the percentages that the gas is made up of.

You're the one who brought up the Nitrox 78 terminology ... perhaps you should ask yourself that question. And if Nitrox always has a higher percentage of nitrogen, as you claim, why then is the course for using percentages up to 100% O2 called "Advanced Nitrox"?

As far as reference is concerned, I'd suggest an older NOAA Manual. The Navy and Commercial industries don't use the EAN terminology either. The only exception to this is with the medical community that will use the term Helio21 (indicating 21% O2). In Diving, Helium mixtures are usually referred to as a 80/20 mix (for example) the first number being Helium.

I don't live in the past ... nor do I teach Navy or Commercial diving. I use terms that are standardized for the industry I work for.

Agreed. That was the essence of what I was saying. A Divemaster with full cave, wanting to use Nitrox, saying that he neglected to bring his Nitrox card with him. I would question him to ascertain his understanding and if everything was OK, let him proceed on the dive. I think that this is reasonable.

What would have been reasonable is for them to clarify their rules ahead of time. Like it or not we live in a litigious society. Businesses have the right to enact any whatever rules they feel need to protect themselves.

... Bob (Grateful Diver)

 

[Superlyte27]

Been running through my IANTD standards. I can't find the req for nitrox in anything lower than Technical Cave. Fulll Cave, Cavern and intro don't seem to require it Nitrox for IANTD.

This website advertises for NSS-CDS Cave, still no nitrox

AZTEC DIVING - COURSES

It's an instructor requirement. And A LOT of instructors in Cave Country require it. BECAUSE: We don't want to shorten your training by making shorter dives and longer surface intervals. Can you imagine training at Ginnie Springs on air with no deco and trying to fit everything in. No thanks. No Nitrox, no class.

 

[MXGratefulDiver]

In most of the Mexico caves, by contrast, nitrox would be a complete waste of money. Several I went into we never hit 30 feet ...

... Bob (Grateful Diver)

 

[DCBC]

just curious, are you saying that EAN50-EAN99 are not Nitrox?

Perhaps you can first tell me of one diving situation where you would use a Nitrox mixture of EAN99? Personally, I've never used a predetermined Nitrox mixture that has had more O2 than N2. How about you?

 

[Wookie]

Perhaps you can first tell me of one diving situation where you would use a Nitrox mixture of EAN99? Personally, I've never used a predetermined Nitrox mixture that has had more O2 than N2. How about you?

I use 80 and 100 all the time.

I bank 80. Try giving a rebreather diver anything less than 100. I have many O/C customers who like 70, 80, and 100 when coming off a shallow/deep dive (180-250 feet) Deeper dives (300-400 feet) they still use a rich gas, but with a very light mix (32) to get off the helium sooner.

I have customers I know have 100 in their pony. They feel more comfortable O2 offgassing on dive 4 and 5 of a multi-day trip. We don't fill them, we don't say anything, we put our fingers in our ears and go La-la-la-la-la, but I know it happens. As long as they don't go into deco, who am I to prevent self-medication?

 

[MXGratefulDiver]

Perhaps you can first tell me of one diving situation where you would use a Nitrox mixture of EAN99? Personally, I've never used a predetermined Nitrox mixture that has had more O2 than N2. How about you?

Routinely ... they're generally used for decompression. EAN50 and EAN80 are commonly used.

... Bob (Grateful Diver)

 

[DCBC]

I'll have to look that up when I get home ... I don't have my standards manual with me at the moment. I do know that wasn't the case when I became an instructor in 2004.

You do that. I've been a NAUI Instructor for a long time before Nitrox was an issue. I don't recollect any change to this policy.

You're the one who brought up the Nitrox 78 terminology ... perhaps you should ask yourself that question. And if Nitrox always has a higher percentage of nitrogen, as you claim, why then is the course for using percentages up to 100% O2 called "Advanced Nitrox"?

Perhaps you should mention which certification agency you're talking about. CMAS has an Advanced Nitrox Program that I also teach. The only difference is that the Advanced program allows a maximum operating depth (MOD) of 54metres (or to the maximum depth permitted by National Standards), subject to a ppO2 maximum of 1.4bar at the MOD. I'd check out the partial pressures and then tell me what mixture you're dealing with.

I don't live in the past ... nor do I teach Navy or Commercial diving. I use terms that are standardized for the industry I work for.

Bob, you asked me for references; I suggested some sources within the research, Naval and Commercial sectors. Nitrox had NO history within the recreational sector. You have to look outside the recreational sector if you want the answers you seek.

What would have been reasonable is for them to clarify their rules ahead of time. Like it or not we live in a litigious society. Businesses have the right to enact any whatever rules they feel need to protect themselves.

Agreed. Business can also elect to use common sense or not. They can treat their customers like crap, if they so desire. Personally, I've found it beneficial to try to be reasonable.

---------- Post added May 16th, 2013 at 07:18 PM ----------

Routinely ... they're generally used for decompression. EAN50 and EAN80 are commonly used.

Who by? I've never used anything higher than EAN50 and O2. For SCUBA purposes it's generally recommended that any mix with greater than 50% O2 be treated as pure O2.

---------- Post added May 16th, 2013 at 07:25 PM ----------

Try giving a rebreather diver anything less than 100. I have many O/C customers who like 70, 80, and 100 when coming off a shallow/deep dive (180-250 feet) Deeper dives (300-400 feet) they still use a rich gas, but with a very light mix (32) to get off the helium sooner.

I use EAN 50 and 100% O2. The Helium isn't a factor for me (it's free). Because of this, I prefer to use Heliox. It doesn't affect me negatively (other than body temp) and I don't have to mess around with N2 percentages. Zero narcosis regardless of depth; nice.

 

[nimoh]

Perhaps you can first tell me of one diving situation where you would use a Nitrox mixture of EAN99? Personally, I've never used a predetermined Nitrox mixture that has had more O2 than N2. How about you?

Nope, never used EAN99. Highest I have used is EAN80. So, I'll rephrase my question. Are you suggesting that EAN50-EAN80 are not Nitrox?

 

[Abdullah]

What I've said IS true Bob. What you choose to believe is up to you. Perhaps you might ask yourself why the term Nitrox I is used and EAN32 isn't called Nitrox 32? It's just a terminology thing when you refer to the percentages that the gas is made up of.

Mixed-gases are based on: Hydrogen (H2): hydreliox and hydrox; Neon (Ne): Neox and Neoquad; Argon (Ar) Argox and argonox; Xeon (Xe): Xenon and Xenonox; Krypton (Kr): Kryptonox. The principal gas is listed first with the lesser gas mentioned later in the term.

As far as reference is concerned, I'd suggest an older NOAA Manual. The Navy and Commercial industries don't use the EAN terminology either. The only exception to this is with the medical community that will use the term Helio21 (indicating 21% O2). In Diving, Helium mixtures are usually referred to as a 80/20 mix (for example) the first number being Helium.

Nitrox is nitrogen and oxygen. Air is 99.998% comprised of nitrogen, oxygen, and argon. Shouldn't air be Nitroxargon 78/21/1?


These are the two references that the US Department of Labor uses (by law) to regulate recreational diving industry employers and work places who use enriched oxygen mixtures in US waters:
2001 National Oceanic and Atmospheric Administration Diving Manual (the “2001 NOAA Diving Manual&#8221
“Enriched Air Operations and Resource Guide” published in 1995 by the Professional Association of Diving Instructors (known commonly as the “1995 DSAT Oxygen Exposure Table)

"(b) Regardless of the diving equipment used, the employer must ensure that no diver exceeds a depth of 130 feet of sea water (“fsw&#8221 or a maximum O2 partial pressure of 1.40 ATA, whichever exposes the diver to less O2 ."

Any US based dive op that employs instructors or dive guides using Nitrox or EAN would need to be on the same "terminology" page as the two references.

BTW, if you're a US dive op and not following these rules, you are regulated by the commercial diving requirements with all the accompanying requirements (chamber availability, equipment requirements, etc.).